Ultra-high density recording with sendust video head and high coercive tape

The recording and the reproducing efficiencies of the advanced sendust video head and a ferrite video head for tapes with coercivities of 700-1700 Oe were examined. It was observed that the recording efficiency of the sendust head is superior to that of the ferrite one, especially for high coercive tape, while the reproducing efficiencies of both heads are comparable. Data is shown which demonstrates the ability of the sendust video head to record on tapes with coercivities up to 1700 Oe without core saturation. Using the sendust head with an extremely narrow gaplength (0.2μm), sine-wave signals of short wavelength (smaller than 0.43μm) were recorded on high coercivity (1450-1700 Oe) tapes and reproduced successfully.